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991.
992.
    
White-rot fungi are considered to be promising biotechnological tools to complement or replace the current technologies for the treatment of effluents from textile production plants. The aim of this work was to investigate the decolorization capacity of Ganoderma weberianum B-18 in solid state fermentation with sugarcane bagasse as a substrate and ligninolytic inducer as well as to decolorize and detoxify industrial effluents by this strain in a laboratory scale packed-bed bio-reactor. The results demonstrated that G. weberianum B-18 indeed showed to possess decolorization capacity in solid state fermentation with sugarcane bagasse supplemented with synthetic dyes. Moreover, fungal biomass of G. weberianum B-18 immobilized in sugarcane bagasse in a packed-bed bioreactor was shown to efficiently decolorize and detoxify different dyes and authentic industrial effluents in semi-continuous conditions. In this decolorization process, laccase enzymes secreted by the fungus played the main role. Hence, a packed-bed reactor with G. weberianum B-18 immobilized in sugarcane bagasse seems to be a suitable system for the further development of an efficient bioprocess for large-scale treatment of dye-containing wastewaters.  相似文献   
993.
    
This paper reports the synthesis and characterization of 2‐(4‐ethoxyphenyl)‐4‐phenyl quinoline (OEt‐DPQ) organic phosphor using an acid‐catalyzed Friedlander reaction and the preparation of blended thin films by molecularly doping OEt‐DPQ in poly(methyl methacrylate) (PMMA) at different wt%. The molecular structure of the synthesized phosphor was confirmed by Fourier transform infra‐red (FTIR) spectroscopy and nuclear magnetic resonance spectra (NMR). Surface morphology and percent composition of the elements were assessed by scanning electron microscopy (SEM) and energy dispersive analysis of X‐rays (EDAX). The thermal stability and melting point of OEt‐DPQ and thin films were probed by thermo‐gravimetric analysis (TGA)/differential thermal analysis (DTA) and were found to be 80°C and 113.6°C, respectively. UV–visible optical absorption spectra of OEt‐DPQ in the solid state and blended films produced absorption bands in the range 260–340 nm, while photoluminescence (PL) spectra of OEt‐DPQ in the solid state and blended thin films demonstrated blue emission that was registered at 432 nm when excited at 363–369 nm. However, solvated OEt‐DPQ in chloroform, tetrahydrofuran or dichloromethane showed a blue shift of 31–43 nm. Optical absorption and emission parameters such as molar extinction coefficient (ε), energy gap (Eg), transmittance (T), reflectance (R), refractive index (n), oscillator energy (E0) and oscillator strength (f), quantum yield (φf), oscillator energy (E0), dispersion energy (Ed), Commission Internationale de l'Éclairage (CIE) co‐ordinates and energy yield fluorescence (EF) were calculated to assess the phosphor's suitability as a blue emissive material for opto‐electronic applications such as organic light‐emitting diodes (OLEDs), flexible displays and solid‐state lighting technology.  相似文献   
994.
    
The investigation of the luminescence properties of CdTe/KBr composites with encapsulated quantum dots (QDs) of different sizes was performed and the influence of the KBr matrix on the luminescence properties of CdTe QDs was studied. Encapsulation of nanoparticles by a solid matrix caused a bathochromic shift in the luminescence peak and the shift value was the larger the smaller the size of the quantum dots. Interband quantum transition theory was used to explain the influence of the matrix on the luminescence properties of the capsulated CdTe QDs. Theoretical calculations showed that the observed QD luminescence peak corresponded to a 1 s–1 s electronic transition, and its low‐energy shift after the transfer of QDs from dielectric water to the KBr matrix was due to a corresponding decrease in the depths of electrons and holes potential wells.  相似文献   
995.
    
Carbon materials are the most promising anodes for sodium‐ion batteries (SIBs), but low initial Coulombic efficiency (ICE) and poor cyclic stability hinder their practical use. It is shown herein, that an effective but simple remedy for these problems can be achieved by deactivating defects in the carbon with Al2O3 nanocluster coverage. A 3D porous graphene monolith (PGM) is used as the model material and Al2O3 nanoclusters around 1 nm are grown on the defects of graphene. It is shown that these Al2O3 nanoclusters suppress the decomposition of conductive sodium salt in the electrolyte, resulting in the formation of a thin and homogenous solid electrolyte interphase (SEI). In addition, Al2O3 nanoclusters appear to reduce the detrimental etching of the SEI by hydrogen fluoride (HF) and improve its stability. Therefore, after the introduction of Al2O3 nanoclusters, the ICE, cyclic stability, and rate capability of the PGM are greatly improved. A higher ICE (70.2%) and capacity retention (82.9% after 500 cycles at 0.5 A g?1) than those of normally reported for large surface area carbons are achieved. This work indicates a new way to deactivate defects and modify the SEI of carbon materials, and hopefully accelerate the commercialization of carbon materials as anode materials for SIBs.  相似文献   
996.
    
Lithium/selenium‐sulfur batteries have recently received considerable attention due to their relatively high specific capacities and high electronic conductivity. Different from the traditional encapsulation strategy for suppressing the shuttle effect, an alternative approach to directly bypass polysulfide/polyselenide formation via rational solid‐electrolyte interphase (SEI) design is demonstrated. It is found that the robust SEI layer that in situ forms during charge/discharge via interplay between rational cathode design and optimal electrolytes could enable solid‐state (de)lithiation chemistry for selenium‐sulfur cathodes. Hence, Se‐doped S22.2Se/Ketjenblack cathodes can attain a high reversible capacity with minimal shuttle effects during long‐term and high rate cycling. Moreover, the underlying solid‐state (de)lithiation mechanism, as evidenced by in situ 7Li NMR and in operando synchrotron X‐ray probes, further extends the optimal sulfur confinement pore size to large mesopores and even macropores that have been long considered as inferior sulfur or selenium host materials, which play a crucial role in developing high volumetric energy density batteries. It is expected that the findings in this study will ignite more efforts to tailor the compositional/structure characteristics of the SEI layers and the related ionic transport across the interface by electrode structure, electrolyte solvent, and electrolyte additive screening.  相似文献   
997.
    
Rechargeable Li‐ion batteries (LIBs) are electrochemical storage device widely applied in electric vehicles, mobile electronic devices, etc. However, traditional LIBs containing liquid electrolytes suffer from flammability, poor electrochemical stability, and limited operational temperature range. Replacement of the liquid electrolytes with inorganic solid‐state electrolytes (SSEs) would solve this problem. However, several critical issues, such as poor interfacial compatibility, low ionic conductivity at ambient temperatures, etc., need to be surmounted before the commercialization of all‐solid‐state Li‐ion batteries (ASSLIBs). In this review, a brief historical context for the inorganic SSEs is described first. Then, two critical issues in the ASSLIBs are highlighted: interfacial incompatibility of the electrodes and SSEs and internal stresses. For the interfacial incompatibility, the discussion is focused on the dynamic characterization of the electrode/SSE interfaces, the origin and evolution of the interfacial resistance, and interface engineering to minimize the interfacial resistance. The internal stresses in the ASSLIBs are another major concern because rigid contacts are introduced. Stress generation, stress evolution during battery cycling, stress measurement/simulation, and ways to alleviate the stresses are outlined in detail. Finally, current challenges and perspectives for future development of the inorganic SSEs and ASSLIBs are outlined.  相似文献   
998.
    
Developing high‐performance batteries through applying renewable resources is of great significance for meeting ever‐growing energy demands and sustainability requirements. Biomaterials have overwhelming advantages in material abundance, environmental benignity, low cost, and more importantly, multifunctionalities from structural and compositional diversity. Therefore, significant and fruitful research on exploiting various natural biomaterials (e.g., soy protein, chitosan, cellulose, fungus, etc.) for boosting high‐energy lithium‐based batteries by means of making or modifying critical battery components (e.g., electrode, electrolyte, and separator) are reported. In this review, the recent advances and main strategies for adopting biomaterials in electrode, electrolyte, and separator engineering for high‐energy lithium‐based batteries are comprehensively summarized. The contributions of biomaterials to stabilizing electrodes, capturing electrochemical intermediates, and protecting lithium metal anodes/enhancing battery safety are specifically emphasized. Furthermore, advantages and challenges of various strategies for fabricating battery materials via biomaterials are described. Finally, future perspectives and possible solutions for further development of biomaterials for high‐energy lithium‐based batteries are proposed.  相似文献   
999.
    
All‐solid‐state lithium metal batteries (ASSLMBs) stand out for the next generation of energy storage system. However, the further realization is severely hampered by the lithium dendrite formation in solid state electrolytes (SSEs), by mechanisms that remain controversial. Herein, with the aid of experimental and theoretical approaches, the origin of dendrite formation in representative LiBH4 SSE, which is thermodynamically stable with the Li metal, suppressing the side reaction between Li and SSE is elucidated. It is demonstrated that upon diffusion, Li+ encounters an electron, and is subsequently reduced to Li0 within the grain boundary/pore of SSE, eventually leading to short circuit. Thus, introducing LiF with the ability of interstitial filling and low electronic conductivity into SSE is the effective countermeasure, and as expected, with the addition of LiF, the critical current density (CCD) increases by 235% compared to the value of pure LiBH4. The TiS2|LiBH4–LiF|Li ASSLMBs manifest a reversible capacity of 137 mAh g?1 at 0.4 C upon 60 cycles. These findings not only unravel critical issues in Li dendrite formation in SSE, but also propose the countermeasure.  相似文献   
1000.
    
The development of all‐solid‐state Li‐ion batteries requires solid electrolyte materials with many desired properties, such as ionic conductivity, chemical and electrochemical stability, and mechanical durability. Computation‐guided materials design techniques are advantageous in designing and identifying new solid electrolytes that can simultaneously meet these requirements. In this joint computational and experimental study, a new family of fast lithium ion conductors, namely, LiTaSiO5 with sphene structure, are successfully identified, synthesized, and demonstrated using a novel computational design strategy. First‐principles computation predicts that Zr‐doped LiTaSiO5 sphene materials have fast Li diffusion, good phase stability, and poor electronic conductivity, which are ideal for solid electrolytes. Experiments confirm that Zr‐doped LiTaSiO5 sphene structure indeed exhibits encouraging ionic conductivity. The lithium diffusion mechanisms in this material are also investigated, indicating the sphene materials are 3D conductors with facile 1D diffusion along the [101] direction and additional cross‐channel migration. This study demonstrates a novel design strategy of activating fast Li ionic diffusion in lithium sphenes, a new materials family of superionic conductors.  相似文献   
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